This invention relates to optical mark readers. In particular, this invention relates to an improved optical mark reader for use in reading marked cards, including test cards, lottery game cards, and similar type cards that contain xe2x80x9cbubblexe2x80x9d or like marks which are filled in with a suitable writing instrument by a user.
Optical mark readers, also known as optical mark recognition devices and bubble card readers, are known in the art. These types of readers are used in a variety of fields, including education and gaming, to read pencil or pen marks that are placed onto a card by a user filling in pre-printed xe2x80x9cbubblesxe2x80x9d on the card. Optical mark readers are typically designed as peripheral units that interface with a local controller, such as a local personal computer, which receives and processes data from the reader, or designed as stand alone units which read and process data within the reader. They may also be connected to local area networks, or even global networks, with suitable interconnection devices.
In the education field, an optical mark reader needs to be highly accurate and reliable in order to provide reliable scoring of test results and the like. Further, the continuing rise in education costs and shrinking education budgets require that the cost of an optical mark reader be as low as possible to allow continued use of such devices within the classroom or school. Moreover, students are often the most frequent users of such readers. Therefore, an optical mark reader should be designed so that it is easy to use.
In some existing optical mark reader designs, the readers are constructed with a large number of parts, including parts that require special manufacturing, thereby increasing the costs of the readers. In addition, the parts are often assembled by hand in assembly line fashion by workers, which further increases costs. A reduction in, and simplification of, the parts of the reader would not only reduce parts costs, but would also reduce manufacturing costs, simplify assembly, improve reliability, and reduce reader size.
Further, many previous optical mark readers have been designed with a relatively narrow input slot through which a card to be read is inserted. Due to the narrow construction of the input slot, the card must be aligned precisely with the slot in order to achieve insertion. However, achieving this level of alignment is time consuming, and can be difficult for some individuals, such as children.
There is a continuing need for an improved optical mark reader that overcomes the aforementioned problems of prior optical mark readers as well as other problems existing with prior art readers.
The invention provides an improved optical mark reader for use in reading or scanning bubble cards. The reader has a reduced number of parts compared to conventional readers, and is simpler to construct and assemble. Moreover, the reader is designed without threaded fasteners. Instead, the reader components are secured to each other using attachment devices that are integral with the various components.
In one aspect of the invention, an optical mark reader is provided. The reader includes a base and an upper housing assembly that define a card path along which a card to be read travels. The base and the upper housing are detachably connected to each other by a quick connect/disconnect fastening system that is integral with the base and the upper housing assembly. By making the base and upper housing assembly readily detachable, debris can be readily removed from the scanning lens and card jams cleared by the reader user, without having the reader serviced by service personnel, and without using cleaning cards which can be expensive. Further, disconnection can be achieved without using tools.
In another aspect of the invention, an optical mark reader is provided that includes a housing having a card path along which a card to be read travels. A scanner is associated with the housing. Further, the card path includes an inlet, and the card path is defined at least in part by a pair of guide walls that are positioned opposite each other, with the guide walls having a height that varies from the inlet to the scanner.
In yet another aspect of the invention, an optical mark reader is provided that includes a housing having a card path along which a card to be read travels. A scanner associated with the housing. The card path includes a tapered inlet through which a card to be read is inserted into the housing, and the inlet tapers both vertically and horizontally. The tapered construction of the inlet makes insertion of a card into the housing easier since a larger insertion area is provided and the taper guides the forward edge of the card into proper alignment for subsequent reading.
In still another aspect of the invention, an optical mark reader for reading bubble cards is provided. The reader includes a housing having a card path along which a card to be read travels. The card path is defined by a pair of guide walls that are spaced apart along at least a portion of the guide path by a distance that is minimally greater than the width of a bubble card. In addition, a scanner is associated with the housing for scanning a card input into the housing. Further, a drive mechanism within the housing transports a card along the card path and through the housing. The drive mechanism includes a single drive wheel disposed adjacent to the scanner and positioned at a decentralized location of the card path. By locating the drive wheel at a decentralized location of the card path, the drive wheel is able to engage a decentralized region of the card where marking does not generally occur. Therefore, the drive wheel will not smear or mar markings on the card, which can potentially lead to inaccurate scanning results.
For a better understanding of the invention, its advantages and objects obtained by its use, reference should be made to the drawings which form a further part hereof, and to the accompanying description, in which there is described a preferred embodiment of the invention.